Method of condensing zinc vapors and collecting the metallic zinc therefrom



(No Model.)

. I I E. WALSH, Jr. METHOD OI CONDENSING ZINC VAPOBS AND COLLECTING THE METALLIC ZINC THEREFR'OM.

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UNITED STATES PAT NT QFFICE.

EDIVARD \VAIJSH, JR, OF ST. LOUIS, MISSOURI.

METHOD OF CONDENSING ZINC VAPORS AND COLLECTING THE METALLIC ZINC THEREFROM.

SPECIFICATION forming part of Letters Patent No; 402,210, dated April 30, 1889;

Application filed November 26, 1888. $erial No. 291,881. (No specimens.)

To all whom it may concern:

Be it known that I, EDWARD WALSH, J r., a citizen of the United States, residing at the city of St. Louis, State of Missouri, have invented a certain new and Improved Method of Condensing Zinc Vapors and Collecting the Metallic Zinc Therefrom, of which the iollowin g is a full, clear, and exact descripion.

My invention relates to a method of condensing zinc vapors and fumes arising from the reduced oxide of zinc in a furnace and collecting the resultant metallic zinc, and is an improvement on the method described in Letters Patent of the United States granted to me on the 14th day of June, 1887,'No. 364,97 9, on which subject it should be here recapitulated that zinc oxide reduces at 1,300 Fahrenheit and the metal distills at about 100 Fahrenheit lower than that temperature. Volatilization takes place immediately on reduction of the zinc oxide. At a temperature of 1,300 Fahrenheit carbon is entirely unaffected by the action of carbonic acidand the carbonic acid generated from the reduction of the zinc oxide is carried off with the zinc vapor at that temperature. Carbonic acid at a temperaturebelow 1,300 Fahrenheit when mixed with zinc vapor again oxidizes the metallic zin c vapor, thereby producing an undesirable result; but I have discovered, that when zinc vapor and carbonic acid, both at a temperature of between 1,400 and 1,500 Fahrenheit,

or slightly in excess of that temperature, are

allowed to pass through carbon or carbonaceous matter which is also at a temperature of between 1, 100 and 1,500 Fahrenheitthe carbonic acid is immediately converted into carbonic oxide, and that thus the zinc vapor does not undergo any further oxidation, that the result-of thus allowingcarbonic acid and zinc vapor at the temperature of between 1,400 and 1,500 Fahrenheit, or slightly in excess of that temperature, to pass through carbon or carbonaceous matter at a temperature between 1,400 and 1,500 Fahrenheit, or slightly in excess of that temperature, is to produce zinc vapor and carbonic oxide.

My present invention consists in first charging a furnace, preferably of the type illustrated in the accompanying drawing, with mixed fuel and ore, in charging carbonaceous matter into the furnace through a chamber or vessel which also serves as a condenser,.and in allowing the zinc vapor and carbonic acid arising from the reduced oxide of zinc in the furnace to pass through carbonaceous matter in this chamber or vessel, whereby the carbonic acid is converted into carbonic oxide and the zinc vapor is preserved from further oxidization, as hereinafter more particularly described, and the zinc vapor passing through the cooler portions of the carbonaceous matter in this chamber or vessel is thereby condensed and precipitated in a liquid form in' this chamber or vessel, whence it is withdrawn through pipes or passages into a trough or other suitably-shaped receiver.

On the accompanying drawing is represented a side sectional elevation of an apparatus used for carrying my invention into effect, the drawing representing my preferable construction.

In the drawing, a represents the furnace, into which the fuel and calcined zinc ores, mixed in such proportions that sufficient fuel is present to eifect a reduction of the zinc oxide, to volatilize the zinc, and fuse the properly fluxed impurities contained in the ore, are charged through the hoppers or chutes b. Projecting externally from and opening into the furnace a at its upper part is a condensing-vessel, c, which is preferably lined with fire-brick, and preferably of a conical form, diminishing from its opening at the furnace at to its outer end, and so arranged that its lower part preferably dips somewhat from the furnace o To the outer end of the condensing-vessel c, and forming a continuation thereof, is preferably fixed a cylinder, d, of cast-iron or other suitable material, into which, at its top por tion, enters a chute, a. closed at its outer end by cover f, formed with a central stuffing-box, g, through which passes a shaft, h, having fixed thereto within the cylinder (Z and of nearly equal diameter to the latter a spiral disk, t, the initial point of which (in the sense of its rotation) is .beneath or somewhat behind the edge of the opening of the chute e.

' Rotation is imparted to the shaft h by a The cylinder d is worm, j, which engages with a worm, 7:, fixed on a shaft, h, externally to the cylinder (1, the worm j being fixed on a shaft, I, mounted in suitable bearings and provided with a pulley, n,which is driven by a belt from any suitable motor adjacent to the apparatus; or the rotation of the shaft 7L may be effected by any other well-known mechanical arrangement, as found most convenient.

Through the lower part of the condensingvessel 0 are a series of passages or pipes, 0, which open below the vessel 0 into a trough, p, or other suitable conduit, for the metallic zinc, as hereinafter referred to.

In operation, the furnace at being charged with the mixed ores and fuel through the chutes Z), and the condensing-vessel 0 charged with carbonaceous matter through the chute e, when the mixed fuel and ore in the furnace a, and the carbonaceous matter lying thereon at and adjacent to the opening of the condensing-vessel a into the furnace a, have reached a temperature of 1,500 Fahrenheit, the zinc vapor and carbonic acid thereby generated from the reduction of the zinc oxide in the furnace a pass through the said portion of the carbonaceous matter into the condensing-vessel c, and in so doing the carbonic acid is immediately converted into carbonic oxide, which passes onward through the cooler portions of the carbonaceous matter in the vessel 0, whereby the zinc vapor is condensed and precipitated in a liquid form to the bottom of the condensing-vessel c, from which it flows from the pipes 0 into the trough or other conduit, 1), and along the latter in any required direction for use, while the carbonic oxide passes from the vessel 0, through the chute e or other pipe, to 'aste or otherwise, as required. Meanwhile the spiral disk '1', being slowly rotated within the cylinder (1, continually forces the carbonaceous matter fed through the chute 6 along the condensing-vessel 0, so that the portion of carbonaceous matter before named, at the open ing into the furnace a, is maintained at the temperature of 1,500 Fahrenheit, or thereabout, necessary for converting the carbonic acid into carbonic oxide, while the temperature of the carbonaceous matter in the vessel 0, behind the said portion, is heated by the gases to the proper temperature for condensing the zinc vapor, or from 1,200 to 800 Fahrenheit.

I have recently filed in the United States Patent Office an application for a patent, in which I claim the apparatus used by me in carrying this method into effect.

\Vhat I here claim as new, and desire to secure by Letters Patent, is

1. The method herein described for preventing the oxidation of zinc vapors and condensing the same into metallic zinc, which consists in passing the mixed zinc vapors, carbonic-acid gases, &c., through a body of carbon, which at its receiving end is at or above a temperature of fifteen hundred degrees (1,500) Fahrenheit and at its discharging end, or where the non-condensable gases and molten zinc escape, at a much lower temperature, substantially as and for the purposes specified.

2. As an improvement in the art of condensing metallic zinc from mixed zinc vapors and oxidizing-gases, subjecting said mixed gases and vapors to a'body of carbon which is fed continuously forward through a chamber heated at its discharge end, or where the carbon is discharged, to a temperature of fifteen hundred degrees (1,500) Fahrenheit, or more, and at its carbon-receiving end, or that where the non-condensable gases escape, at or below a temperature at which zinc vapors will condense into liquid molten zinc, the mixed vapors and gases being passed in a reverse direction to the passage or travel of the carbon or condensing medium, substantially as and for the purposes specified.

In testimony whereof I affix my signature, in presence of two witnesses, this 23d day of November, 1888.

EDWARD WALSH, J'R.

Witnesses:

L. SCHRADER, PAUL BAKEWELL. 

